Method for creating incision to improve intraocular lens placement

ABSTRACT

A system and method for inserting an intraocular lens in a patient&#39;s eye includes a light source for generating a light beam, a scanner for deflecting the light beam to form an enclosed treatment pattern that includes a registration feature, and a delivery system for delivering the enclosed treatment pattern to target tissue in the patient&#39;s eye to form an enclosed incision therein having the registration feature. An intraocular lens is placed within the enclosed incision, wherein the intraocular lens has a registration feature that engages with the registration feature of the enclosed incision. Alternately, the scanner can make a separate registration incision for a post that is connected to the intraocular lens via a strut member.

RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.14/163,550, filed Jan. 24, 2014, and issued as U.S. Pat. No. 9,820,848on Nov. 21, 2017 which is a divisional of U.S. application Ser. No.12/703,689, filed Feb. 10, 2010 and issued as U.S. Pat. No. 8,657,810 onFeb. 25, 2014, which is a divisional of U.S. application Ser. No.12/048,182, filed Mar. 13, 2008 and issued as U.S. Pat. No. 8,518,026 onAug. 27, 2013, which claims the benefit of U.S. Provisional ApplicationNo. 60/906,944, filed Mar. 13, 2007. All of the above-referencedapplications are incorporated herein by reference in their entireties.

FIELD OF THE INVENTION

The present invention relates to ophthalmic surgical procedures andsystems.

BACKGROUND OF THE INVENTION

Cataract extraction is one of the most commonly performed surgicalprocedures in the world with estimated 2.5 million cases performedannually in the United States and 9.1 million cases worldwide in 2000.This was expected to increase to approximately 13.3 million estimatedglobal cases in 2006. This market is composed of various segmentsincluding intraocular lenses for implantation, viscoelastic polymers tofacilitate surgical maneuvers, disposable instrumentation includingultrasonic phacoemulsification tips, tubing, and various knives andforceps. Modern cataract surgery is typically performed using atechnique termed phacoemulsification in which an ultrasonic tip with anassociated water stream for cooling purposes is used to sculpt therelatively hard nucleus of the lens after performance of an opening inthe anterior lens capsule termed anterior capsulotomy or more recentlycapsulorhexis. Following these steps as well as removal of residualsofter lens cortex by aspiration methods without fragmentation, asynthetic foldable intraocular lens (IOL) is inserted into the eyethrough a small incision.

One of the earliest and most critical steps in the procedure is theperformance of capsulorhexis. This step evolved from an earliertechnique termed can-opener capsulotomy in which a sharp needle was usedto perforate the anterior lens capsule in a circular fashion followed bythe removal of a circular fragment of lens capsule typically in therange of 5-8 mm in diameter. This facilitated the next step of nuclearsculpting by phacoemulsification. Due to a variety of complicationsassociated with the initial can-opener technique, attempts were made byleading experts in the field to develop a better technique for removalof the anterior lens capsule preceding the emulsification step. Theconcept of the capsulorhexis is to provide a smooth continuous circularopening through which not only the phacoemulsification of the nucleuscan be performed safely and easily, but also for easy insertion of theintraocular lens. It provides both a clear central access for insertion,a permanent aperture for transmission of the image to the retina by thepatient, and also a support of the IOL inside the remaining capsule thatwould limit the potential for dislocation.

Using the older technique of can-opener capsulotomy, or even with thecontinuous capsulorhexis, problems may develop related to inability ofthe surgeon to adequately visualize the capsule due to lack of redreflex, to grasp it with sufficient security, to tear a smooth circularopening of the appropriate size without radial rips and extensions ortechnical difficulties related to maintenance of the anterior chamberdepth after initial opening, small size of the pupil, or the absence ofa red reflex due to the lens opacity. Some of the problems withvisualization have been minimized through the use of dyes such asmethylene blue or indocyanine green. Additional complications arise inpatients with weak zonules (typically older patients) and very youngchildren that have very soft and elastic capsules, which are verydifficult to mechanically rupture.

Many cataract patients are astigmatic. Astigmatism can occur when thecornea has a different curvature one direction than the other. IOLS areused for correcting astigmatism but require precise placement,orientation, and stability. Complete and long lasting correction usingIOLs is difficult. Further, IOLs are not presently used to correctbeyond 5D of astigmatism, even though many candidates have more severeaberrations. Correcting it further often involves making the cornealshape more spherical, or at least more radially symmetrical. There havebeen numerous approaches, including Comeaplasty, Astigmatic Keratotomy(AK), Corneal Relaxing Incisions (CRI), and Limbal Relaxing Incisions(LRI). All are done using manual, mechanical incisions. Presently,astigmatism cannot easily or predictably be fully corrected. About onethird of those who have surgery to correct the irregularity find thattheir eyes regress to a considerable degree and only a small improvementis noted. Another third find that the astigmatism has been significantlyreduced but not fully corrected. The remaining third have the mostencouraging results with the most or all of the desired correctionachieved.

What is needed are ophthalmic methods, techniques and apparatus toadvance the standard of care of the astigmatic cataract patient.

SUMMARY OF THE INVENTION

The present invention provides methods and apparatus to precisely andaccurately seat an IOL within the capsule of an eye of a patient byusing a short pulse laser to create a capsular incision whose size andshape complement that of the IOL itself. This can be accomplished byadding asymmetrical features to the incision and lens, or portionsthereof.

A method of inserting an intraocular lens in a patient's eye includesgenerating a light beam, deflecting the light beam using a scanner toform an enclosed treatment pattern that includes a registration feature,delivering the enclosed treatment pattern to target tissue in thepatient's eye to form an enclosed incision therein having theregistration feature, and placing an intraocular lens within theenclosed incision, wherein the intraocular lens has a registrationfeature that engages with the registration feature of the enclosedincision.

A method of inserting an intraocular lens in a patient's eye includesgenerating a light beam, deflecting the light beam using a scanner toform an enclosed treatment pattern and a registration pattern,delivering the enclosed treatment pattern and the second pattern totarget tissue in the patient's eye to form an enclosed incision and aregistration incision therein, placing an intraocular lens within theenclosed incision, placing a post within the registration incision, andconnecting the post to the intraocular lens using at least one strutmember.

Other objects and features of the present invention will become apparentby a review of the specification, claims and appended figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of the optical beam scanning system.

FIG. 2 is an optical diagram showing an alternative beam combiningscheme.

FIG. 3 is a schematic diagram of the optical beam scanning system withan alternative OCT configuration.

FIG. 4 is a schematic diagram of the optical beam scanning system withanother alternative OCT combining scheme.

FIG. 5 is a top view diagram of a rotationally asymmetric capsulorhexisincision.

FIG. 6 is a top view diagram of a complementary rotationally asymmetricIOL.

FIG. 7 is a top view the IOL of FIG. 6 positioned in the capsule of FIG.5.

FIGS. 8 and 9 are side views of the rotationally asymmetric IOL of FIG.6.

FIG. 10 is a top view diagram of a rotationally asymmetric capsulorhexisincision.

FIG. 11 is a top view diagram of a complementary rotationally asymmetricIOL.

FIG. 12 is a top view of the IOL of FIG. 11 positioned in the capsule ofFIG. 10.

FIG. 13 is a top view diagram of a rotationally asymmetric capsulorhexisincision.

FIG. 14 is a top view shows a diagram of a complementary rotationallyasymmetric IOL.

FIG. 15 is a top view diagram of a rotationally asymmetric capsulorhexisincision.

FIG. 16 is a top view diagram of a complementary rotationally asymmetricIOL.

FIG. 17 is a perspective view of the rotationally asymmetric IOL of FIG.16.

FIG. 18 is a side view of the rotationally asymmetric IOL of FIG. 16.

FIG. 19 is a top view diagram of a rotationally asymmetric IOL.

FIG. 20 is a top view diagram of a rotationally asymmetric IOL.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The techniques and systems disclosed herein provide many advantages overthe current standard of care. Specifically, rapid and precise openingsin the lens capsule are enabled using 3-dimensional patterned lasercutting to facilitate the placement and stability of intraocular lenses.

Another procedure enabled by the techniques described herein providesfor the controlled formation of an incision in the anterior and/orposterior lens capsule. Conventional procedures require a completecircle or nearly complete circular cut. Openings formed usingconventional, manual capsulorhexis techniques rely primarily on themechanical shearing properties of lens capsule tissue and uncontrollabletears of the lens capsule to form openings. These conventionaltechniques are confined to the central lens portion or to areasaccessible using mechanical cutting instruments and to varying limiteddegrees utilize precise anatomical measurements during the formation ofthe tears. In contrast, the controllable, patterned laser techniquesdescribed herein may be used to create an incision in virtually anyposition in the anterior and/or posterior capsule(s) and in virtuallyany shape. In “Bag-in-the-lens” surgery, matching incisions must be madein both the anterior and posterior capsules to fit the IOL in place. Thepresent invention is uniquely suited to perform such matching incisions.

Furthermore, these capsular incisions may be tailored or keyed toaccommodate an asymmetric IOL that requires it to be preciselypositioned in both its location and rotational orientation. Moreover,the controllable, patterned laser techniques described herein also haveavailable and/or utilize precise lens capsule size, measurement andother dimensional information that allows the incision or openingformation while minimizing impact on surrounding tissue.

The present invention can be implemented by a system that projects orscans an optical beam into a patient's eye 68, such as system 2 shown inFIG. 1 which includes an ultrafast (UF) light source 4 (e.g. afemtosecond laser). Using this system, a beam may be scanned in apatient's eye in three dimensions: X, Y, Z. In this embodiment, the UFwavelength can vary between 1010 nm to 1100 nm and the pulse width canvary from 100 fs to 10000 fs. The pulse repetition frequency can alsovary from 10 kHz to 250 kHz. Safety limits with regard to unintendeddamage to non-targeted tissue bound the upper limit with regard torepetition rate and pulse energy; while threshold energy, time tocomplete the procedure and stability bound the lower limit for pulseenergy and repetition rate. The peak power of the focused spot in theeye 68 and specifically within the crystalline lens 69 and anteriorcapsule of the eye is sufficient to produce optical breakdown andinitiate a plasma-mediated ablation process. Near-infrared wavelengthsare preferred because linear optical absorption and scattering inbiological tissue is reduced across that spectral range. As an example,laser 4 may be a repetitively pulsed 1035 nm device that produces 500 fspulses at a repetition rate of 100 kHz and an individual pulse energy inthe ten microjoule range.

The laser 4 is controlled by control electronics 300, via an input andoutput device 302, to create optical beam 6. Control electronics 300 maybe a computer, microcontroller, etc. In this example, the entire systemis controlled by the controller 300, and data moved through input/outputdevice IO 302. A graphical user interface GUI 304 may be used to setsystem operating parameters, process user input (UI) 306 on the GUI 304,and display gathered information such as images of ocular structures.

The generated UF light beam 6 proceeds towards the patient eye 68passing through half-wave plate, 8, and linear polarizer, 10. Thepolarization state of the beam can be adjusted so that the desiredamount of light passes through half-wave plate 8 and linear polarizer10, which together act as a variable attenuator for the UF beam 6.Additionally, the orientation of linear polarizer 10 determines theincident polarization state incident upon beamcombiner 34, therebyoptimizing beamcombiner throughput.

The UF beam proceeds through a shutter 12, aperture 14, and a pickoffdevice 16. The system controlled shutter 12 ensures on/off control ofthe laser for procedural and safety reasons. The aperture sets an outeruseful diameter for the laser beam and the pickoff monitors the outputof the useful beam. The pickoff device 16 includes of a partiallyreflecting mirror 20 and a detector 18. Pulse energy, average power, ora combination may be measured using detector 18. The information can beused for feedback to the half-wave plate 8 for attenuation and to verifywhether the shutter 12 is open or closed. In addition, the shutter 12may have position sensors to provide a redundant state detection.

The beam passes through a beam conditioning stage 22, in which beamparameters such as beam diameter, divergence, circularity, andastigmatism can be modified. In this illustrative example, the beamconditioning stage 22 includes a 2 element beam expanding telescopecomprised of spherical optics 24 and 26 in order to achieve the intendedbeam size and collimation. Although not illustrated here, an anamorphicor other optical system can be used to achieve the desired beamparameters. The factors used to determine these beam parameters includethe output beam parameters of the laser, the overall magnification ofthe system, and the desired numerical aperture (NA) at the treatmentlocation. In addition, the optical system 22 can be used to imageaperture 14 to a desired location (e.g. the center location between the2-axis scanning device 50 described below). In this way, the amount oflight that makes it through the aperture 14 is assured to make itthrough the scanning system. Pickoff device 16 is then a reliablemeasure of the usable light.

After exiting conditioning stage 22, beam 6 reflects off of fold mirrors28, 30, & 32. These mirrors can be adjustable for alignment purposes.The beam 6 is then incident upon beam combiner 34. Beamcombiner 34reflects the UF beam 6 (and transmits both the OCT 114 and aim 202 beamsdescribed below). For efficient beamcombiner operation, the angle ofincidence is preferably kept below 45 degrees and the polarization wherepossible of the beams is fixed. For the UF beam 6, the orientation oflinear polarizer 10 provides fixed polarization.

Following the beam combiner 34, the beam 6 continues onto the z-adjustor Z scan device 40. In this illustrative example the z-adjust includesa Galilean telescope with two lens groups 42 and 44 (each lens groupincludes one or more lenses). Lens group 42 moves along the z-axis aboutthe collimation position of the telescope. In this way, the focusposition of the spot in the patient's eye 68 moves along the z-axis asindicated. In general there is a fixed linear relationship between themotion of lens 42 and the motion of the focus. In this case, thez-adjust telescope has an approximate 2× beam expansion ratio and a 1:1relationship of the movement of lens 42 to the movement of the focus.Alternatively, lens group 44 could be moved along the z-axis to actuatethe z-adjust, and scan. The z-adjust is the z-scan device for treatmentin the eye 68. It can be controlled automatically and dynamically by thesystem and selected to be independent or to interplay with the X-Y scandevice described next. Mirrors 36 and 38 can be used for aligning theoptical axis with the axis of z-adjust device 40.

After passing through the z-adjust device 40, the beam 6 is directed tothe x-y scan device by mirrors 46 & 48. Mirrors 46 & 48 can beadjustable for alignment purposes. X-Y scanning is achieved by thescanning device 50 preferably using two mirrors 52 & 54 under thecontrol of control electronics 300, which rotate in orthogonaldirections using motors, galvanometers, or any other well known opticmoving device. Mirrors 52 & 54 are located near the telecentric positionof the objective lens 58 and contact lens 66 combination describedbelow. Tilting these mirrors 52/54 causes them to deflect beam 6,causing lateral displacements in the plane of UF focus located in thepatient's eye 68. Objective lens 58 may be a complex multi-element lenselement, as shown, and represented by lenses 60, 62, and 64. Thecomplexity of the lens 58 will be dictated by the scan field size, thefocused spot size, the available working distance on both the proximaland distal sides of objective 58, as well as the amount of aberrationcontrol. An f-theta lens 58 of focal length 60 mm generating a spot sizeof 10 μm, over a field of 10 mm, with an input beam size of 15 mmdiameter is an example. Alternatively, X-Y scanning by scanner 50 may beachieved by using one or more moveable optical elements (e.g. lenses,gratings) which also may be controlled by control electronics 300, viainput and output device 302.

The aiming and treatment scan patterns can be automatically generated bythe scanner 50 under the control of controller 300. Such patterns may becomprised of a single spot of light, multiple spots of light, acontinuous pattern of light, multiple continuous patterns of light,and/or any combination of these. In addition, the aiming pattern (usingaim beam 202 described below) need not be identical to the treatmentpattern (using light beam 6), but preferably at least defines itsboundaries in order to assure that the treatment light is delivered onlywithin the desired target area for patient safety. This may be done, forexample, by having the aiming pattern provide an outline of the intendedtreatment pattern. This way the spatial extent of the treatment patternmay be made known to the user, if not the exact locations of theindividual spots themselves, and the scanning thus optimized for speed,efficiency and accuracy. The aiming pattern may also be made to beperceived as blinking in order to further enhance its visibility to theuser.

An optional contact lens 66, which can be any suitable ophthalmic lens,can be used to help further focus the optical beam 6 into the patient'seye 68 while helping to stabilize eye position. The positioning andcharacter of optical beam 6 and/or the scan pattern the beam 6 forms onthe eye 68 may be further controlled by use of an input device such as ajoystick, or any other appropriate user input device (e.g. GUI 304) toposition the patient and/or the optical system.

The UF laser 4 and controller 300 can be set to target the surfaces ofthe targeted structures in the eye 68 and ensure that the beam 6 will befocused where appropriate and not unintentionally damage non-targetedtissue. Imaging modalities and techniques described herein, such as forexample, Optical Coherence Tomography (OCT), Purkinje imaging,Scheimpflug imaging, or ultrasound may be used to determine the locationand measure the thickness of the lens and lens capsule to providegreater precision to the laser focusing methods, including 2D and 3Dpatterning. Laser focusing may also be accomplished using one or moremethods including direct observation of an aiming beam, OpticalCoherence Tomography (OCT), Purkinje imaging, Scheimpflug imaging,ultrasound, or other known ophthalmic or medical imaging modalitiesand/or combinations thereof. In the embodiment of FIG. 1, an OCT device100 is described, although other modalities are within the scope of thepresent invention. An OCT scan of the eye will provide information aboutthe axial location of the anterior and posterior lens capsule, theboundaries of the cataract nucleus, as well as the depth of the anteriorchamber. This information is then be loaded into the control electronics300, and used to program and control the subsequent laser-assistedsurgical procedure. The information may also be used to determine a widevariety of parameters related to the procedure such as, for example, theupper and lower axial limits of the focal planes used for cutting thelens capsule and segmentation of the lens cortex and nucleus, and thethickness of the lens capsule among others.

The OCT device 100 in FIG. 1 includes a broadband or a swept lightsource 102 that is split by a fiber coupler 104 into a reference arm 106and a sample arm 110. The reference arm 106 includes a module 108containing a reference reflection along with suitable dispersion andpath length compensation. The sample arm 110 of the OCT device 100 hasan output connector 112 that serves as an interface to the rest of theUF laser system. The return signals from both the reference and samplearms 106, 110 are then directed by coupler 104 to a detection device128, which employs either time domain, frequency or single pointdetection techniques. In FIG. 1, a frequency domain technique is usedwith an OCT wavelength of 920 nm and bandwidth of 100 nm.

Exiting connector 112, the OCT beam 114 is collimated using lens 116.The size of the collimated beam 114 is determined by the focal length oflens 116. The size of the beam 114 is dictated by the desired NA at thefocus in the eye and the magnification of the beam train leading to theeye 68. Generally, OCT beam 114 does not require as high an NA as the UFbeam 6 in the focal plane and therefore the OCT beam 114 is smaller indiameter than the UF beam 6 at the beamcombiner 34 location. Followingcollimating lens 116 is aperture 118 which further modifies theresultant NA of the OCT beam 114 at the eye. The diameter of aperture118 is chosen to optimize OCT light incident on the target tissue andthe strength of the return signal. Polarization control element 120,which may be active or dynamic, is used to compensate for polarizationstate changes which may be induced by individual differences in cornealbirefringence, for example. Mirrors 122 & 124 are then used to directthe OCT beam 114 towards beamcombiners 126 & 34. Mirrors 122 & 124 maybe adjustable for alignment purposes and in particular for overlaying ofOCT beam 114 to UF beam 6 subsequent to beamcombiner 34. Similarly,beamcombiner 126 is used to combine the OCT beam 114 with the aim beam202 described below.

Once combined with the UF beam 6 subsequent to beamcombiner 34, OCT beam114 follows the same path as UF beam 6 through the rest of the system.In this way, OCT beam 114 is indicative of the location of UF beam 6.OCT beam 114 passes through the z-scan 40 and x-y scan 50 devices thenthe objective lens 58, contact lens 66 and on into the eye 68.Reflections and scatter off of structures within the eye provide returnbeams that retrace back through the optical system, into connector 112,through coupler 104, and to OCT detector 128. These return backreflections provide the OCT signals that are in turn interpreted by thesystem as to the location in X, Y Z of UF beam 6 focal location.

OCT device 100 works on the principle of measuring differences inoptical path length between its reference and sample arms. Therefore,passing the OCT through z-adjust 40 does not extend the z-range of OCTsystem 100 because the optical path length does not change as a functionof movement of 42. OCT system 100 has an inherent z-range that isrelated to the detection scheme, and in the case of frequency domaindetection it is specifically related to the spectrometer and thelocation of the reference arm 106. In the case of OCT system 100 used inFIG. 1, the z-range is approximately 1-2 mm in an aqueous environment.Extending this range to at least 4 mm involves the adjustment of thepath length of the reference arm within OCT system 100. Passing the OCTbeam 114 in the sample arm through the z-scan of z-adjust 40 allows foroptimization of the OCT signal strength. This is accomplished byfocusing the OCT beam 114 onto the targeted structure whileaccommodating the extended optical path length by commensuratelyincreasing the path within the reference arm 106 of OCT system 100.

Because of the fundamental differences in the OCT measurement withrespect to the UF focus device due to influences such as immersionindex, refraction, and aberration, both chromatic and monochromatic,care must be taken in analyzing the OCT signal with respect to the UFbeam focal location. A calibration or registration procedure as afunction of X, Y Z should be conducted in order to match the OCT signalinformation to the UF focus location and also to the relate to absolutedimensional quantities.

Observation of an aim beam may also be used to assist the user todirecting the UF laser focus. Additionally, an aim beam visible to theunaided eye in lieu of the infrared OCT and UF beams can be helpful withalignment provided the aim beam accurately represents the infrared beamparameters. An aim subsystem 200 is employed in the configuration shownin FIG. 1. The aim beam 202 is generated by a an aim beam light source201, such as a helium-neon laser operating at a wavelength of 633 nm.Alternatively a laser diode in the 630-650 nm range could be used. Theadvantage of using the helium neon 633 nm beam is its long coherencelength, which would enable the use of the aim path as a laser unequalpath interferometer (LUPI) to measure the optical quality of the beamtrain, for example.

Once the aim beam light source generates aim beam 202, the aim beam 202is collimated using lens 204. The size of the collimated beam isdetermined by the focal length of lens 204. The size of the aim beam 202is dictated by the desired NA at the focus in the eye and themagnification of the beam train leading to the eye 68. Generally, aimbeam 202 should have close to the same NA as UF beam 6 in the focalplane and therefore aim beam 202 is of similar diameter to the UF beamat the beamcombiner 34 location. Because the aim beam is meant tostand-in for the UF beam 6 during system alignment to the target tissueof the eye, much of the aim path mimics the UF path as describedpreviously. The aim beam 202 proceeds through a half-wave plate 206 andlinear polarizer 208. The polarization state of the aim beam 202 can beadjusted so that the desired amount of light passes through polarizer208. Elements 206 & 208 therefore act as a variable attenuator for theaim beam 202. Additionally, the orientation of polarizer 208 determinesthe incident polarization state incident upon beamcombiners 126 and 34,thereby fixing the polarization state and allowing for optimization ofthe beamcombiners' throughput. Of course, if a semiconductor laser isused as aim beam light source 200, the drive current can be varied toadjust the optical power.

The aim beam 202 proceeds through a shutter 210 and aperture 212. Thesystem controlled shutter 210 provides on/off control of the aim beam202. The aperture 212 sets an outer useful diameter for the aim beam 202and can be adjusted appropriately. A calibration procedure measuring theoutput of the aim beam 202 at the eye can be used to set the attenuationof aim beam 202 via control of polarizer 206.

The aim beam 202 next passes through a beam conditioning device 214.Beam parameters such as beam diameter, divergence, circularity, andastigmatism can be modified using one or more well known beamingconditioning optical elements. In the case of an aim beam 202 emergingfrom an optical fiber, the beam conditioning device 214 can simplyinclude a beam expanding telescope with two optical elements 216 and 218in order to achieve the intended beam size and collimation. The finalfactors used to determine the aim beam parameters such as degree ofcollimation are dictated by what is necessary to match the UF beam 6 andaim beam 202 at the location of the eye 68. Chromatic differences can betaken into account by appropriate adjustments of beam conditioningdevice 214. In addition, the optical system 214 is used to imageaperture 212 to a desired location such as a conjugate location ofaperture 14.

The aim beam 202 next reflects off of fold mirrors 222 & 220, which arepreferably adjustable for alignment registration to UF beam 6 subsequentto beam combiner 34. The aim beam 202 is then incident upon beamcombiner 126 where the aim beam 202 is combined with OCT beam 114.Beamcombiner 126 reflects the aim beam 202 and transmits the OCT beam114, which allows for efficient operation of the beamcombining functionsat both wavelength ranges. Alternatively, the transmit and reflectfunctions of beamcombiner 126 can be reversed and the configurationinverted. Subsequent to beamcombiner 126, aim beam 202 along with OCTbeam 114 is combined with UF beam 6 by beamcombiner 34.

A device for imaging the target tissue on or within the eye 68 is shownschematically in FIG. 1 as imaging system 71. Imaging system includes acamera 74 and an illumination light source 86 for creating an image ofthe target tissue. The imaging system 71 gathers images which may beused by the system controller 300 for providing pattern centering aboutor within a predefined structure. The illumination light source 86 forthe viewing is generally broadband and incoherent. For example, lightsource 86 can include multiple LEDs as shown. The wavelength of theviewing light source 86 is preferably in the range of 700 nm to 750 nm,but can be anything which is accommodated by the beamcombiner 56, whichcombines the viewing light with the beam path for UF beam 6 and aim beam202 (beamcombiner 56 reflects the viewing wavelengths while transmittingthe OCT and UF wavelengths). The beamcombiner 56 may partially transmitthe aim wavelength so that the aim beam 202 can be visible to theviewing camera 74. Optional polarization element 84 in front of lightsource 86 can be a linear polarizer, a quarter wave plate, a half-waveplate or any combination, and is used to optimize signal. A false colorimage as generated by the near infrared wavelength is acceptable.

The illumination light from light source 86 is directed down towards theeye using the same objective lens 58 and contact lens 66 as the UF andaim beam 6, 202. The light reflected and scattered off of variousstructures in the eye 68 are collected by the same lenses 58 & 66 anddirected back towards beamcombiner 56. There, the return light isdirected back into the viewing path via beam combiner and mirror 82, andon to camera 74. Camera 74 can be, for example but not limited to, anysilicon based detector array of the appropriately sized format. Videolens 76 forms an image onto the camera's detector array while opticalelements 80 & 78 provide polarization control and wavelength filteringrespectively. Aperture or iris 81 provides control of imaging NA andtherefore depth of focus and depth of field. A small aperture providesthe advantage of large depth of field which aids in the patient dockingprocedure. Alternatively, the illumination and camera paths can beswitched. Furthermore, aim light source 200 can be made to emit in theinfrared which would not directly visible, but could be captured anddisplayed using imaging system 71.

Coarse adjust registration is usually needed so that when the contactlens 66 comes into contact with the cornea, the targeted structures arein the capture range of the X, Y scan of the system. Therefore a dockingprocedure is preferred, which preferably takes in account patient motionas the system approaches the contact condition (i.e. contact between thepatient's eye 68 and the contact lens 66. The viewing system 71 isconfigured so that the depth of focus is large enough such that thepatient's eye 68 and other salient features may be seen before thecontact lens 66 makes contact with eye 68.

Preferably, a motion control system 70 is integrated into the overallcontrol system 2, and may move the patient, the system 2 or elementsthereof, or both, to achieve accurate and reliable contact betweencontact lens 66 and eye 68. Furthermore, a vacuum suction subsystem andflange may be incorporated into system 2, and used to stabilize eye 68.The alignment of eye 68 to system 2 via contact lens 66 may beaccomplished while monitoring the output of imaging system 71, andperformed manually or automatically by analyzing the images produced byimaging system 71 electronically by means of control electronics 300 viaIO 302. Force and/or pressure sensor feedback may also be used todiscern contact, as well as to initiate the vacuum subsystem.

An alternative beamcombining configuration is shown in the alternateembodiment of FIG. 2. For example, the passive beamcombiner 34 in FIG. 1can be replaced with an active combiner 140 in FIG. 2. The activebeamcombiner 34 can be a moving or dynamically controlled element suchas a galvanometric scanning mirror, as shown. Active combiner 140changes it angular orientation in order to direct either the UF beam 6or the combined aim and OCT beams 202,114 towards the scanner 50 andeventually eye 68 one at a time. The advantage of the active combiningtechnique is that it avoids the difficulty of combining beams withsimilar wavelength ranges or polarization states using a passive beamcombiner. This ability is traded off against the ability to havesimultaneous beams in time and potentially less accuracy and precisiondue to positional tolerances of active beam combiner 140.

Another alternate embodiment is shown in FIG. 3 which is similar to thatof FIG. 1 but utilizes an alternate approach to OCT 100. In FIG. 3, OCT101 is the same as OCT 100 in FIG. 1, except that the reference arm 106has been replaced by reference arm 132. This free-space OCT referencearm 132 is realized by including beamsplitter 130 after lens 116. Thereference beam 132 then proceeds through polarization controllingelement 134 and then onto the reference return module 136. The referencereturn module 136 contains the appropriate dispersion and path lengthadjusting and compensating elements and generates an appropriatereference signal for interference with the sample signal. The sample armof OCT 101 now originates subsequent to beamsplitter 130. The potentialadvantages of this free space configuration include separatepolarization control and maintenance of the reference and sample arms.The fiber based beam splitter 104 of OCT 101 can also be replaced by afiber based circulator. Alternately, both OCT detector 128 andbeamsplitter 130 might be moved together as opposed to reference arm136.

FIG. 4 shows another alternative embodiment for combining OCT beam 114and UF beam 6. In FIG. 4, OCT 156 (which can include either of theconfigurations of OCT 100 or 101) is configured such that its OCT beam154 is coupled to UF beam 6 after the z-scan 40 using beamcombiner 152.In this way, OCT beam 154 avoids using the z-adjust. This allows the OCT156 to possibly be folded into the beam more easily and shortening thepath length for more stable operation. This OCT configuration is at theexpense of an optimized signal return strength as discussed with respectto FIG. 1. There are many possibilities for the configuration of the OCTinterferometer, including time and frequency domain approaches, singleand dual beam methods, swept source, etc, as described in U.S. Pat. Nos.5,748,898; 5,748,352; 5,459,570; 6,111,645; and 6,053,613 (which areincorporated herein by reference.)

FIGS. 5 through 9 illustrate different aspects of an embodiment of thepresent invention, which can be implemented using the scanning system 2described above. As shown in FIG. 5, a capsulorhexis incision 400 (whichmay be created using system 2) is tailored for astigmatism-correctingintraocular lenses (IOLs). Such astigmatism-correcting IOLs need to beplaced not only at the correct location within the capsule 402 of theeye 68, but also oriented at the correct rotational/clocking angle.Thus, they have inherent rotational asymmetries, unlike spherical IOLs.The incision 400 shown in this example is elliptical, however, othershapes are also useful. Incision 400 may be made continuously, orpiecewise to largely maintain the structural integrity of thelens-capsule apparatus of the patient's eye 68. Such incompleteincisions 400 may be thought of as perforated incisions, and may be madeto be removed gently in order to minimize their potential toinadvertently extend the capsulorhexis. Either way, incision 400 is anenclosed incision, which for the purposes of this disclosure means thatit starts and ends at the same location and encircles a certain amountof tissue therein. The simplest example of an enclosed incision is acircular incision, where a round piece of tissue is encircled by theincision. It follows therefore that an enclosed treatment pattern (i.e.generated by system 2 for forming an enclosed incision) is one that alsostarts and ends at the same location and defines a space encircledthereby.

One key feature of the enclosed incision 400 is that it includes aregistration feature to orient the IOL that will be placed inside it.For the illustrated elliptical incision 400, it elliptical shape is it'sregistration feature, which allows for the accurate placement of an IOLby virtue of its inherent rotational asymmetry, unlike the desiredcircular outcome of a manual CCC. The elliptical major axis 404 andminor axis 406 of incision 400 are shown. Major axis 404 and minor axis406 are not equal. Incision 400 may be made at any rotational anglerelative to the eye 68 of a patient, although it is shown in thisexample to be in the plane of the iris with its major axis 404 lyingalong the horizontal. Incision 400 is intended to mate with one or morecomplementary registration features on an IOL. The ranging subsystem ofsystem 2 (e.g. the OCT 100 subsystem) may be used to precisely definethe surface of the capsule 402 to be incised. This may serve to isolatethe laser pulses nominally to the vicinity of the targeted capsule 402itself, thus minimizing the energy required and the treatment time andcommensurately increasing patient safety and overall efficiency.

As shown in FIG. 6, an IOL 408 includes an optic portion 410 used tofocus light and a haptic 416 used to position the IOL 408. Optic 410 isa rotationally asymmetric lens (about its optical axis) that include anelliptically shaped peripheral sidewall or edge 412, the complementaryregistration feature that mates with elliptically shaped incision 400.In this example, the elliptically shaped edge 412 includes a major axis418 and minor axis 420. Major axis 418 and minor axis 420 are not equal.Intraocular lens IOL 408 further contains surface 414 that serves tohold haptics element 416 and provide a resting place for capsule 402 tosecure optic 410 of intraocular lens 408 in the proper orientation andposition within the capsule 402 of a patient's eye 68. Surface 414 isshown as elliptical, but need not be. Haptics 416 provide stability andmay serve to seat edge 412 of intraocular lens 408 in incision 400 byapplying retaining force towards the anterior portion of capsule 402.Haptics 416 may be deployed in any orientation. The orientation of thecylindrical correction of optic 410 of intraocular lens 408 may be madeto coincide with either its major axis 418 or its minor axis 420. Inthis way, intraocular lenses IOL 408 and optic 410 may be manufacturedin a standardized manner and the rotational orientation of incision 400and the spherical and cylindrical optical powers of optic 410 may bemade to vary to suit the individual optical prescription of the eye 68of a patient.

FIG. 7 shows the proper immediate disposition of intraocular lens 408once installed into capsule 402 with mating registration features edge412 and incision 400 engaged, and resting upon surface 414. Major axis404 and major axis 418 are not of equal length. Minor axis 406 and minoraxis 420 are not the same length, either. This is done to accommodatethe fact the capsule 402 may contract somewhat subsequent tocapsulorhexis incision. The difference between the lengths of these axesis intended to allow the capsule 402 to contract and still better seatintraocular lens 408 into capsule 402 via incision 400. Thesedifferences should be limited to allow for reasonable contraction, butnot so much as to allow for significant rotation of intraocular lens408. Typical values for these length differences may range from 100 μmto 500 μm, for example.

FIG. 8 shows a side view on the same intraocular lens 408 depicted inFIGS. 6 and 7. In this schematic representation, edge 412 is shown onthe same side of optic 410 as surface 424 of intraocular lens 408. Thesurface 422 on intraocular lens 408 serves to maintain the integrity offit between edge 412 and incision 400. Edge 412 is seen as theprojection of surface 422 in the alternate view depicted in FIGS. 6 and7. Optical axis 411 of optic 410 is shown. Haptics 416 lie along theline of sight in this view.

FIG. 9 is a side view of the lens configuration of FIG. 8, but rotated90 degrees to show that displaying surface 426 is not curved in bothdirections (i.e. shaped as a cylindrical lens). This cylindrical ortoric optical system of optic 410 provides cylindrical correction forthe astigmatism of a patient. Haptics 416 lie perpendicular to the lineof sight in this view.

FIG. 10 shows an alternate embodiment similar to the asymmetry of theexample of FIG. 6, except that incision 400 includes a registrationfeature 428 formed as a notch extending from the otherwise roundincision 400. Registration feature 428 serves to provide a means tolocate a matching registration feature (i.e. a protrusion) onintraocular lens 410. The complementary registration feature 430 of IOL408 including optic 410 is illustrated in FIG. 11. The shape ofregistration feature 428 is shown as half round for illustrativepurposes only. Alternately, a teardrop shape, such as that shown in FIG.15, for edge 412 and incision 400 is less likely to contain sharp edgesand thus be less prone to inadvertent extension of the capsulorhexis.Many similar complementary shapes are possible and within the scope ofthe present invention. A benefit of the short pulse laser systemdescribed in FIG. 1 is that it may provide via a plasma-mediatedablation process smooth incisions 400 that are unlikely to extend.

In FIG. 11, registration feature 430 is intended to mate withregistration feature 428 of incision 400. This serves to correctlylocate optic 410 and maintain its rotational integrity. Here again edge412 and surface 414 provide features to assure mechanical stability andproper orientation with respect to the capsule 402 of a patient's eye68. Similar to the FIG. 6 description of the asymmetric major axes 404 &418, registration feature 430 may be placed at an arbitrary rotationalorientation to suit an individual prescription. Haptics 416 may bedeployed in any orientation, as before.

FIG. 12 shows the proper immediate disposition of intraocular lens 408once installed into capsule 402 via incision 400 with mating featureedge 412 engaged, similar to that shown in FIG. 7.

FIG. 13 shows an alternate embodiment similar to that of FIGS. 6 & 10with the addition of a registration incision 432 (formed by aregistration pattern of treatment light generated by system 2) that isseparate and distinct from capsulorhexis incision 400. As before,registration incision 432 serves to provide a means to locate a matchingregistration feature on intraocular lens 408.

FIG. 14 shows an alternate embodiment similar to that of FIG. 11, withpost 434 that sits in the registration incision 432 and atop strut 436away from optic 410 on intraocular lens 408. Post 434 and strut 436 areshown as being tilted away from the normal between haptics 416, but neednot be. Many such similar complementary configurations are possible andwithin the scope of the present invention.

IOL 408 can also mate with the capsulorhexis incision by way of acircumferential flange. The shape of the capsulorhexis incision 400 maybe made to orient the IOL 408 to achieve cylindrical corrections, asshown schematically in FIG. 15. The asymmetric incision 400 of FIG. 15is similar to that of FIGS. 5, 10 and 13 with the addition that it isintended to mate with a flange on intraocular lens 408 rather than anedge 412 and a surface 414.

FIG. 16 shows intraocular lens 408 utilizing a flange 438 to mate withincision 400. As shown, intraocular lens 408 is comprised of optic 410and flange 438. This flange 438 may be circumferential, as shown, butneed not be. It may simply lie atop optic 410 and serve the same purposeof mating and retaining intraocular lens 408 within capsule 402. Flange438 contains groove 440 to seat the capsule 402 in incision 400.Rotationally asymmetric groove 440 serves to accurately position andretain intraocular lens 408 within incision 400 at the correctrotational orientation for the individual astigmatic prescription. Thisoptical correction is achieved using optic 410. Alternately, groove 440may be a created between flange 438 and optic 410 (rather than withinflange 438, as shown) when flange 438 lies atop intraocular lens 408.Such an intraocular lens 408 may be used in “bag-in-the-lens” surgeries.

FIGS. 17 and 18 show the same configuration as that of FIG. 16, but fromdifferent viewing perspectives to better illustrate groove 440. Groove440 may be made to engage incision 400 continuously, as shown, ordiscontinuously by providing notches cut into flange 438. Such notchesmay serve to more easily initiate the engagement of flange 438 withcapsule 402 via incision 400. Alternately, flange 438 could be made suchthat the depth between its edge and groove 440 varies along itscircumference. This way, a region of shallow depth could be used as astarting point for more easily engaging intraocular lens 408 withcapsule 402 via incision 400.

FIG. 19 shows an alternate embodiment that is similar to that of FIG.16, but where optic 410 may be made to rotate within flange 438. Toalign the rotation of optic 410, angular alignment marks 444 aredisplayed on flange 438 and a complementary alignment mark 446 isdisplayed on optic 410. In this manner, intraocular lens 408 and optic410 may be manufactured in a standardized manner and one may rotateoptic 410 relative to its surrounding flange 438 to provide astigmaticcorrection to suit the individual prescription. Alignment marks 444 areshown at 22.5° intervals, but may be otherwise. Alignment marks 444 and446 may be etched into the materials of their host elements, oralternately imprinted upon them.

FIG. 20 shows one further alternate embodiment that is similar to thatof FIGS. 14 and 19, where optic 410 may be made to rotate within ring448. In this illustrative example, post 434 and strut 436 are integralto optic 410, and contain alignment mark 446. Ring 448 contains haptics416 and surface 414 as before but now also alignment marks 444.Alignment mark 446 on strut 436 of optic 410 facilitates the rotationalorientation of astigmatic correcting optic 410. In this manner, theultimate orientation of intraocular lens 408 within capsule 402 of theeye of a patient via incision 400 that may be made in any orientation.Many such similar complementary configurations are possible and withinthe scope of the present invention.

It is to be understood that the present invention is not limited to theembodiment(s) described above and illustrated herein, but encompassesany and all variations falling within the scope of the appended claims.For example, references to the present invention herein are not intendedto limit the scope of any claim or claim term, but instead merely makereference to one or more features that may be covered by one or more ofthe claims. All the optical elements downstream of scanner 50 shown inFIGS. 1, 3 and 4 form a delivery system of optical elements fordelivering the beam 6, 114 and 202 to the target tissue. Conceivably,depending on the desired features of the system, some or even most ofthe depicted optical elements could be omitted in a delivery system thatstill reliably delivers the scanned beams to the target tissue.Protrusion registrations features could be replaced with indentations(i.e. notches), and vice versa.

What is claimed is:
 1. An intraocular lens for replacing a natural lensin a lens capsule of a patient's eye, the intraocular lens comprising: alens portion shaped for focusing light passing therethrough; wherein thelens portion includes a peripheral edge in a plan view perpendicular toan axis of the lens portion that entirely surrounds the lens portion andthat forms one and only one registration feature configured to mate withone or more complementary registration features created on the lenscapsule so as to orient the intraocular lens, the peripheral edge havinga circular shape except in one and only one region having the one andonly one registration feature, the registration feature being a singleprotrusion extending radially from the peripheral edge and having arounded edge; and an outer portion disposed around the lens portion andextends radially in the plan view to a circumferential outer edge thatis outside of the entire peripheral edge of the lens portion includingthe registration feature, the outer portion including a surface which istransverse to the axis of the lens portion and located adjacent to theperipheral edge of the lens portion.
 2. The intraocular lens of claim 1,further comprising at least two haptics extending from the outer edge ofthe outer portion for supplying a spring force to the lens portion.